University of Wisconsin–Madison

Use of Ferumoxytol as a Negative and Positive MR Contrast Agent

April 2015 to December 2015

Ultra-small superparamagnetic iron oxide particle (USPIO), ferumoxytol, has strong T1 and T2 shortening effects as well as a high susceptibility effect. Early reports in the literature demonstrate that this agent can be used as either a positive (ie: bright) or negative (ie: dark) contrast agent. It has the distinct advantage of not containing gadolinium, and therefore patients with renal failure can undergo ferumoxytol-enhanced MRI without concerns of contracting Nephrogenic Systemic Fibrosis (NSF). Despite its off-label use, preliminary studies in the literature suggest that ferumoxytol-enhanced T1-weighted MRA with positive contrast can provide sufficient anatomical information. Further, ferumoxytol is taken up in the reticuloendothelial system (RES), which leads to negative contrast in normal lymph nodes and liver. This phenomenon can be exploited to distinguish lymph nodes with metastatic disease (which appear bright despite injection of ferumoxytol) from normal lymph nodes, as well as liver metastasis from liver parenchyma.
The aims of this study are 1) To validate the utility of ferumoxytol-enhanced T1-weighted MRA using gadolinium-enhanced MRA as the standard of reference, and to optimize MR parameters, 2) To accurately quantify negative contrast effects in the liver and lymph nodes by ferumoxytol injection by measurement of T1, T2 using MRS (liver), and T2* values using IDEAL-IQ (liver and lymph nodes), 3) To test the above with two different doses of ferumoxytol, and at two different field strengths (1.5 and 3T), and 4) To assess the pharmacokinetics of ferumoxytol to optimize its use as a negative contrast agent.

This project led by: Scott B Reeder, MD, PhD